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Comment by KerrAvon | Hacker News Reader

Your questions don't make sense. LLVM is a framework for building compilers and tools. C is a language specification.

It does make sense, your language can target C or LLVM. each option comes with pros and cons e.g: C is more familiar, LLVM has better support for JIT compilation.

No it doesn't. Ignoring the fact that you incorrectly refer to LLVM IR as LLVM, C is a language spec and LLVM IR is a dialect. LLVM IR dialect doesn't mean much outside LLVM framework and are constantly expanded upon and improved via no attributes and ops and abstractions to help trickle down context coming from levels above to be used for optimizations and making valid assumptions down the line. Comparing the 2 is nonsensical to say the least.

I know what you mean. But the fact is that there are compiler front-ends which produce LLVM IR, and there are compiler front-ends which produce C, so they alternatives to each other in that context.

And what do you do with that produced C program?

Both C and llvm have been used as backends for other language implementations so it makes sense to compare them for that use case.

>> Ignoring the fact that you incorrectly refer to LLVM IR as LLVM

I also "incorrectly" wrote "target C" instead of "target C code". It's obvious what I meant.

>> Comparing the 2 is nonsensical to say the least.

You could have easily googled "C vs LLVM as a backend" to find a lot of interesting discussions comparing both before being so confidently incorrect

Thank you. I'm thoroughly confused not only by the question, but by the amount of replies treating this as a valid question. Maybe I'm misinterpreting something here...

I agree the question is not well formed, but it’s easier to understand if you read this story (OP mentioned but did not link):

https://news.ycombinator.com/item?id=36529456

Basically the Zig language is moving away from using LLVM in its backend. One backend they are adding is one that generates C.

I guess if I had to restate the OP’s question, I would say:

What are the trade offs in making a compiler target LLVM versus C in its backend.

Reply on news.ycombinator.com